const myTarget = {};

const proxy = new Proxy(myTarget, {
    defineProperty(target, property, receiver) {
        console.log('defineProperty()');
        return Reflect.defineProperty(...arguments);
    }
});

Object.defineProperty(proxy, 'foo', {value: 'bar'});

console.log(Object.defineProperty(proxy, 'bar', {value: 'baz'}))